diff --git a/cmtj/__init__.pyi b/cmtj/__init__.pyi
index 99b316f..0909e61 100644
--- a/cmtj/__init__.pyi
+++ b/cmtj/__init__.pyi
@@ -38,7 +38,7 @@ def gaussianImpulseDriver(
 
     Formula:
 
-    $A * \exp(-(t - t_0)^2 / (2\sigma^2))$
+    $A \exp(-(t - t_0)^2 / (2\sigma^2))$
 
     :param constantValue: offset of the pulse (vertical)
     :param amplitude: amplitude that is added on top of the constantValue
diff --git a/core/stack.hpp b/core/stack.hpp
index 4b1e472..e35a125 100644
--- a/core/stack.hpp
+++ b/core/stack.hpp
@@ -265,16 +265,17 @@ template <typename T> class Stack {
           if (this->delayed) {
             // accumulate coupling
             effectiveCoupling *= (1 + this->getEffectiveCouplingStrength(
-                                          j - 1, frozenMags[j],
-                                          frozenMags[j - 1], frozenPols[j]));
+                                          j - 1, frozenMags[j - 1],
+                                          frozenMags[j], frozenPols[j - 1]));
 
           } else {
             effectiveCoupling *=
-                (1 +
-                 this->getEffectiveCouplingStrength(
-                     j - 1, junctionList[j].getLayerMagnetisation(this->topId),
-                     junctionList[j - 1].getLayerMagnetisation(this->topId),
-                     junctionList[j].getLayerMagnetisation(this->bottomId)));
+                (1 + this->getEffectiveCouplingStrength(
+                         j - 1,
+                         junctionList[j - 1].getLayerMagnetisation(this->topId),
+                         junctionList[j].getLayerMagnetisation(this->topId),
+                         junctionList[j - 1].getLayerMagnetisation(
+                             this->bottomId)));
           }
         }